5-18-17 11:04 AM EST: "Abraham Lincoln, a one-time U.S. representative from Illinois, is nominated for the U.S. presidency by the Republican National Convention meeting in Chicago, Illinois. Hannibal Hamlin of Maine was nominated for the vice presidency.

Lincoln, a Kentucky-born lawyer and former Whig representative to Congress, first gained national stature during his campaign against Democratic Senator Stephen Douglas of Illinois for a U.S. Senate seat in 1858. The senatorial campaign featured a remarkable series of public encounters on the slavery issue, known as the Lincoln-Douglas debates, in which Lincoln argued against the spread of slavery while Douglas maintained that each territory should have the right to decide whether it would become free or slave. Lincoln lost the Senate race, but his campaign brought national attention to the young Republican Party. In 1860, Lincoln won the party’s presidential nomination.

In the November election, Lincoln again faced Douglas, who represented the Northern faction of a heavily divided Democratic Party, as well as Southern Democrat John C. Breckinridge and Constitutional Union candidate John Bell. On November 6, 1860, Lincoln defeated his opponents with only 40 percent of the popular vote, becoming the first Republican to win the presidency. The announcement of Lincoln’s victory signaled the secession of the Southern states, which since the beginning of the year had been publicly threatening secession if the Republicans gained the White House.

By the time of Lincoln’s inauguration on March 4, 1861, seven states had seceded, and the Confederate States of America had been formally established, with Jefferson Davis as its elected president. One month later, the American Civil War began when Confederate forces under General P.G.T. Beauregard opened fire on Union-held Fort Sumter in South Carolina." (quoted from History.com)